Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Nasal vaccination with attenuated Salmonella expressing VapA: TLR2 activation is not essential for protection against R. equi infection

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Virulent strains of Rhodococcus equi have a large plasmid of 80-90 kb, which encodes several virulence-associated proteins (yap), including VapA, a lipoprotein highly associated with disease. We have previously demonstrated that oral immunisation with attenuated Salmonella enterica Typhimurium strain expressing the antigen VapA (STM VapA+) induces specific and long-term humoral and cellular immunity against R. equi. It was shown that VapA activates Toll-like receptor 2 (TLR2) on macrophages by establishing an interaction that ultimately favours immunity against R. equi infection. The purpose of this study was to evaluate the immune response triggered by nasal immunisation with STM VapA+ and to determine whether TLR2 supports the vaccine effect. We developed an optimised protocol for a single nasal immunisation that conferred protection against R. equi infection in mice, which was manifested by efficient R. equi clearance in challenged animals. Nasal vaccination with STM VapA+ has also induced protection in Tlr2(-/-) mice and mice with non-functional TLR4. Moreover, spleen cells of vaccinated mice augmented T-bet expression, as well as the production of IL-12, IFN-gamma, nitric oxide and hydrogen peroxide. Notably, the population of CD4(+) T cells with memory phenotype significantly increased in the spleens of vaccinated mice challenged 1 or 5 months after immunisation. In these animals, the spleen bacterial burden was also reduced. When similar experimental procedures were performed in TLR2 knockout mice, an increase in CD4(+) T cells with memory phenotype was not observed. Consequently, we conclude that nasal vaccination with attenuated Salmonella expressing the R. equi virulence factor VapA confers long-lasting protection against experimental rhodoccocosis and that TLR2 engagement was not crucial to induce this protection but may be required for a long-term immune response. (C) 2013 Elsevier Ltd. All rights reserved.314145284535Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FAPESP [05/50460-1]CNPq [154963/2006-2

Accelerometer-Derived Activity Phenotypes in Young Adults: a Latent Class Analysis.

Purpose: To identify “activity phenotypes” from accelerometer-derived activity characteristics among young adults. Methods: Participants were young adults (n = 628, mean age, 22.1, SD 0.6) in the Raine Study in Western Australia. Sex-specific latent class analyses identified sub-groups using eight indicators derived from 7-day hip-worn Actigraph GT3X+ accelerometers: daily steps, total daily moderate-to-vigorous physical activity (MVPA), MVPA variation, MVPA intensity, MVPA bout duration, sedentary-to-light ratio, sedentary-to-light ratio variation, and sedentary bout duration. Results: Five activity phenotypes were identified for women (n = 324) and men (n = 304). Activity phenotype 1 for both women (35%) and men (30%) represented average activity characteristics. Phenotype 2 for women (17%) and men (16%) was characterized by below average total activity and MVPA (10.6 and 16.7 min of MVPA/day, women and men respectively). Phenotype 3 for women (15%) and men (23%) was characterized by below average total physical activity, average MVPA (32.6 and 36.5 min/day), high sedentary-light ratio and long sedentary bouts. Phenotype 4 differed between women (29%) and men (18%) but both had low sedentary-to-light ratios and shorter sedentary bouts. Finally, phenotype 5 in both women (4%) and men (12%) was characterized by extreme MVPA metrics (81.3 and 96.1 min/day). Conclusions: Five activity phenotypes were identified for each gender in this population of young adults which can help design targeted interventions to enhance or modulate activity phenotypes